This invention covers the acid addition salt of 3,4-dihydro5-methyl-6-(2-methylpropyl)-4-oxothieno[2,3-d]pyrimidine-2-carb oxylic acid with N-methyl-D-glucamine containing a base to acid molecular ratio of 1:1. The compound of this invention is classified in general as a drug, bio-affecting and body-treating type of compound. The acid component of the subject salt is referred to herein by code number MJ 12175 and is represented by the following structural formula. ##STR1##
D. L. Temple, Jr., U.S. Pat. Nos. 4,054,656 and 4,159,377 describe preparation of MJ 12175, its use as an antiallergic agent, and the potassium salt thereof. The latter is advantageous because of its improved water solubility, but solutions thereof are not desirable for nasal instillation because of their alkaline pH. As stated therein, MJ 12175 may be used for antiallergenic purposes in the form of the acid or its metal salts. Accordingly, exemplifications are given therein directed to salts of the alkali metals sodium and potassium. To achieve a rapid response with an antiallergic substance for therapeutic purposes a dosage form is required which can be administered topically to mucous membranes. This in general requires presentation of the drug as a non-irritating solution or dry powder, the solution being preferable due to less difficulty in controlling the dosage when given, for example, as a nasal instillation.
Accordingly, the primary object of the present invention is to provide a water-soluble, stable, therapeutically acceptable form of an antiallergic agent MJ 12175 which can be administered topically. This object as well as other features and advantages of the invention will be readily apparent to those skilled in the art from the disclosure set out below and accompanying claims.